Redirecting old website to newer one

Hello,

I’m moving a site from mainsite.com to sub.mainsite.com

but when a user is loading the page mainsite.com/hello/world

can i have that user redirected to sub.mainsite.com/hello/world

??
and it’s not just one page.. it’s over a 100, so it would be painful to add all one by one.

Hope the plugin can help with that!

Thanks alot